How can I calculate how much my rooftop solar can generate in a day?
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To estimate how much electricity your solar system can generate in a day, you need a few key pieces of information:
The total DC capacity of your solar system (in kW)
The average number of peak sunlight hours in your area (also called solar irradiation)
Just multiply your system size by the peak sunlight hours to get the theoretical daily generation.
For example, if you have a 3 kW system and your area gets 5 hours of good sunlight daily, then:
3 kW × 5 hours = 15 units (kWh) per day (theoretical)
However, in real-world conditions, solar systems usually operate at about 78% to 80% efficiency due to energy losses (from wiring, inverter, dust on panels, etc.).
So, you can expect around 20% less generation than the theoretical figure.
Using the example above, the actual generation would be about: